WO2007104257A1

WO2007104257A1 - An axial plunger pump or motor

Info

Publication number: WO2007104257A1
Application number: PCT/CN2007/000807
Authority: WO
Inventors: Ronghui Zhu
Original assignee: Zhu Raphael
Priority date: 2006-03-14
Filing date: 2007-03-13
Publication date: 2007-09-20
Also published as: KR20090020549A; CN101415944A; JP2009529619A; CN101415944B; EP2012010A1; US20090007773A1

Abstract

An axial plunger pump or motor includes a casing (1), a main shaft (2), a cylinder (14), a swash plate (9), some plunger assemblies (10). A constant velocity universal coupling (11) transfers torque between the main shaft and the rotating swash plate, and then the main shaft and the swash plate rotate around the axes of the main shaft or the swash plate respectively. The conversation between the hydraulic energy and the rotation mechanical energy is realized.

Description

Axial piston pump or motor

The present invention relates to a hydraulic pump or motor device in a hydraulic machine, particularly an axial piston pump or motor.

Background technique

In hydraulic machines, a hydraulic pump or motor is the heart of a hydraulic device. In theory, the hydraulic pump and the motor can be switched to each other, only in some local differences. Therefore, only the structure of the motor of the pump is substantially the same as that of the present specification. The plunger pump is widely used in construction machinery due to its high efficiency, high pressure and easy variable adjustment.

The plunger pump is divided into an axial piston pump and a radial piston pump according to the direction of the plunger stroke, and is divided into a swash plate type plunger pump and a slanting shaft type according to the mechanism of motion conversion in the axial piston pump. The plunger pump has the structural features shown in Figures 1-3.

The swash plate type axial piston pump is a variable pressure pump with high pressure, high speed, impact resistance and high integration. As shown in Fig. 1 and Fig. 2, the power is driven by the main shaft through the involute spline to rotate the rotor evenly. The plurality of plungers on the rotor press the slide of the plunger assembly against the plane of the friction plate of the swash plate through the ball joint and the pressing plate. Since the swash plate plane has an inclination angle with respect to the rotation axis, the plunger body not only works with the rotor The rotary motion also reciprocates along the plunger hole of the rotor to achieve oil absorption and oil supply of the plunger pump. Adjust the inclination of the swash plate plane to change the stroke of the plunger and adjust the variables. Changing the direction of the swashplate tilt can change the direction of the high pressure oil or the direction of rotation of the rotor as a hydraulic motor.

The swashplate type axial piston pump has easy adjustment of the variables, and can easily switch between high pressure oil direction, rotor rotation direction, and pump and motor status. The structure is relatively simple, small in size and low in cost. However, the swashplate type axial piston pump has three main frictional motions: the rotor and the oil distribution plate, the plunger and plunger holes, the plunger slide and the swash plate. Between the plunger and the plunger hole, due to the normal force exerted by the plunger on the swash plate, the plunger receives axial force while also having tangential force and moment, the force and force. The moment is balanced by the pressure of the plunger through the rotor plunger bore, and the sliding friction under the force and moment will lead to a reduction in mechanical efficiency and wear of the component. The rotor is also subject to the effect of the turning moment requiring a central shaft support or an external bearing to balance. Therefore, there are three problems in the pump: First, the overall efficiency is relatively low: the volumetric efficiency of the oil pump is about 0.92 ~ 0. 98, the mechanical efficiency is between 0. 90-0. 95, the total efficiency <= 0. 95; Second, it is sensitive to oil pollution, the pump has a short life; the third is that the rotation speed is not high.

As shown in Figure 3, the working principle of the inclined-axis piston pump and the swash plate pump is quite similar, but there are large differences in the structure. In addition, the force is also different. The inclined shaft pump replaces the shoe and the swash plate in the swash plate pump with the hinged plunger ball head, which improves the strength and impact resistance of the structure. When the pump is working, because the angle between the axis of the connecting rod and the axis of the plunger is not large, the side pressure between the plunger and the cylinder wall is much smaller than that of the swash plate pump, so not only the wear is small, but also The inclination angle β can also be increased to 25 - 30 (the swash plate pump is not more than 20), which expands the range of flow variation. Moreover, the inclined shaft pump drive shaft has a small size or does not pass through the oil distribution plate, so that the diameter of the red body rotor is correspondingly reduced, and the leakage and friction loss are reduced, so the overall efficiency of the inclined shaft pump is higher than that of the swash plate pump, The process level is 2-3% higher than the swash plate pump. The pump's oil absorption performance is also improved by the reduction of the cylinder's peripheral speed, and the pump's limit speed can be increased accordingly. The accuracy of the inclined shaft pump oil filter is low, generally 25 m, and the swash plate pump is 10 ~ 15 m.

Due to the above advantages, the application of the inclined shaft pump in hydraulic machinery is increasing. However, the pump is variable by the oscillating cylinder, and the outer shape is large; the deflection between the rotor and the power shaft makes the outer corner shape, which is not conducive to the narrow space and the place where the meat shaft assembly is required; the structure and the process are relatively complicated. The cost is also high. Summary of the invention

It is an object of the present invention to provide an axial piston pump or motor that can increase the efficiency of a plunger pump or motor, simplify construction, reduce volume, reduce cost, and expand the range of applications of a plunger pump or motor, particularly It can be used in places with special installation requirements such as motor vehicle transmissions.

The above object of the present invention can be achieved by the following technical solution, an axial piston pump or motor, comprising: case;

a spindle that is rotatably supported on the housing;

a rotor cylinder having a plurality of plunger holes, coupled to the main shaft, driven by the main shaft to rotate about the main shaft, and the rotor red body has an oil distribution end surface;

An oil distribution plate, which cooperates with an oil distribution end surface of the rotor cylinder;

a swash plate having an end surface axially disposed opposite to the plurality of plunger holes of the rotor cylinder and rotatable about an axis of the swash plate at an angle to the axis of the spindle;

a plurality of plunger assemblies, one end of which is hinged to the end surface of the swash plate, and the other end of which is slidably disposed in the plunger hole of the rotor cylinder;

The constant velocity universal joint is disposed between the swash plate and the main shaft, and the constant velocity universal joint transmits torque between the main shaft and the swash plate, so that the main shaft and the swash plate are respectively disposed at an angle The spindle axis and the swashplate axis rotate.

In the present invention, the constant velocity universal joint can be a ball cage type constant velocity universal joint, a half angle cage type constant velocity universal joint, a ball joint type constant velocity universal joint or Ball fork type constant velocity universal joint.

The ball cage type constant velocity universal joint in the invention comprises an inner ring with an outer ballway, an even number of steel balls, a cage and an outer ring with an inner ballway, and the steel ball is mounted on the cage and located inside In the fairway and the outer fairway, the inner cymbal is coupled to the main shaft, and the outer cymbal is coupled to the swash plate, so that the main shaft and the swash plate are respectively clamped by the ball cage type constant velocity universal joint The spindle axis of the corner and the swashplate axis rotate.

In the present invention, as a specific example, the outer ring may be integrally formed on the swash plate.

In the present invention, as an alternative example, the swash plate may be supported on the housing by a swash plate bearing.

In the present invention, as another optional example, the swash plate may be supported on a wobble plate by a swash plate bearing, and the wobble plate is supported on the housing by a wobble plate bearing, and the wobble plate bearing is The axis of rotation is perpendicular to the spindle axis and passes through the center of the constant velocity universal coupling. In the above example, a variable adjustment mechanism for adjusting the deflection angle of the wobble plate may be connected to the wobble plate, so that the swash plate axis and the spindle axis of the swash plate supported thereon are changed by the change of the deflection angle of the wobble plate. The angle changes, the stroke of the plunger assembly is changed, and the variable is adjusted.

As an alternative example, the variable adjustment mechanism of the present invention may be a variable cylinder whose piston is coupled to the wobble plate to drive the wobble plate deflection by the expansion and contraction of the piston.

As another optional example, the variable adjustment mechanism is an trunnion type variable mechanism including a trunnion coupled to the wobble plate and a drive mechanism for driving the trunnion, the axis of rotation of the trunnion and the axis of rotation of the wobble plate Coincident, thereby driving the wobble plate deflection by rotating the trunnion.

In the present invention, the rotor cylinder is tapered, and the diameter of one end adjacent to the swash plate is larger than the diameter of the other end.

In the above example, the plurality of plunger holes on the rotor cylinder are also tapered, wherein the diameter of the hole of the plunger hole at the mating end of the plunger assembly is larger than the diameter of the plunger hole at the other end. Round diameter.

In the present invention, the plunger assembly may be specifically a ball joint plunger assembly including a ball joint rod and a plunger having a ball end at both ends, and a ball is provided on an end surface of the swash plate a ball end, the ball end of one end of the ball joint is disposed in the ball socket to form a ball joint connection with the swash plate, and the other end ball head is disposed in the plunger to form a ball joint connection with the plunger, the plunger slidingly disposed on the column In the plug hole, an oil hole communicating with the plunger hole is opened in the middle of the ball joint link and the plunger, thereby introducing the pressure oil to lubricate the ball ends at both ends.

In the present invention, the hinge centers of the plurality of plunger assemblies on the swash plate are located on the same plane, and the intersection of the plane and the spindle axis coincides with the center of the constant velocity universal joint.

In the present invention, an oil distribution plate is disposed at a rear end of the rotor rainbow body, and the rotor cylinder body is axially positioned on the main shaft by a compression spring and a compression spring retaining ring, and an oil hole and a diameter are opened at an end portion of the main shaft. To the oil passage, the pressure between the rotor cylinder and the oil distribution plate is adjusted by injecting pressure oil into the radial oil passage.

In the present invention, as an alternative embodiment, the oil distribution end surface of the rotor cylinder may be a spherical surface, and the oil distribution plate of the rotor body forms a spherical fit with the oil distribution end surface.

In the present invention, the swash plate bearing may be a needle bearing and a cylindrical or tapered roller thrust bearing Combined bearing. The wobble bearing of the present invention can be a crescent-shaped needle bearing.

According to the above structure of the present invention, the axial piston pump or the motor of the present invention can drive the swash plate around the swash plate at an angle with the spindle axis by the constant velocity universal joint while the main shaft drives the rotor to rotate the rainbow body. The axis rotates, thereby driving the plunger assembly to reciprocate in the plunger hole of the rotor cylinder to form a volume change in the cylinder body, and is connected with the inlet and outlet ports successively under the cooperation of the oil distribution plate at the rear end of the rotor cylinder block. The process of oil absorption and oil pressure, that is, the conversion between rotational mechanical energy and hydraulic energy is achieved. The swash plate is rotated by the shaft, so that the variable adjustment can be easily realized by changing the inclination of the swash plate by the variable mechanism driving the wobble plate.

The axial piston pump or motor of the present invention has the following effects as compared with the conventional swash plate type axial piston pump or motor and the oblique shaft axial piston pump or motor:

A) Compared with the variable swash pump: Since the ball joint plunger assembly and the swash plate are used instead of the swash plate and the swash plate in the swash plate pump, the three pairs of main friction corresponding to the swash plate pump are paid, Great changes have taken place: 1. The sliding friction between the plunger slide and the swash plate is converted into rolling friction, friction and leakage are reduced; and the surface area of the ball joint forming the ball joint is larger than the diameter of the same diameter sliding disk The radial dimension of the swash plate is reduced. 2. The friction pair between the plunger and the plunger hole wall of the rotor cylinder. Since the side pressure is much smaller than that of the swash plate pump, the friction is naturally reduced, and the precision of the oil filter is also required. Significantly reduced, wear reduction; 3. Friction pair between rotor cylinder and oil distribution plate, because the spindle does not bear bending moment, only support at the rotor end, the size can be reduced, so that the rotor cylinder can be matched with oil. The port diameter is correspondingly reduced, the port circumference and relative motion linear velocity are reduced, and frictional power consumption and leakage are reduced. In addition, the pump swashplate tilt angle β can be increased to 25° - 30. (The swash plate pump is no more than 20 °), which expands the range of flow fluctuation, reduces the size of the pump, and improves the oil absorption performance of the pump due to the decrease of the circumferential speed of the cylinder. At the same time, the hydraulic thrust of the plunger is passed. The ball head, the swash plate, the bearing and the wobble plate support are transferred directly to the housing, so that the moving parts such as the main shaft and the rotor block are not subjected to other additional forces or moments, the force structure of the moving parts is improved, friction is reduced and leakage. The effects of many of the above factors are:

1) The overall efficiency is higher than that of the swash plate pump. 2) Improved structural strength, impact resistance, oil resistance, reduced wear and increased life.

3) The limit speed of the pump or motor is increased.

4) The size of the pump or motor is further reduced.

B), compared with the variable oblique-axis pump, although the construction of the synchronous constant velocity universal coupling, with a certain efficiency loss (usually 1-3%), has achieved four major benefits:

1) Volume and weight reduction: By adjusting the deflection of the wobble plate instead of the swing of the rotor body, the radial dimension required for the same deflection angle is reduced; due to the change of the force mode, the original power shaft is subjected to a large bending moment while withstanding the torque. The function must have a certain axial length to balance, so the power shaft is long; and the rear oil distribution plate, the swash plate and the variable adjustment mechanism also occupy a large space. With the same parameters, the new variable-column pump reduces axial length and radial size by more than 1/3 compared to conventional inclined-shaft pumps.

2) Achieve coaxial or through-shaft transmission: Suitable for some space installations with limited size, coaxial transmission or through-shaft transmission requirements, such as multi-pump series, in some applications, the mechanical system can be cylinderized or optimized.

3) Adjusting the switch tube is convenient: Change the tilt angle of the wobble plate to adjust the flow output size, change the tilt direction to change the flow direction or switch between the pump and the motor. The original inclined-axis plunger pump has a large stroke space and driving force to achieve.

4) Further improvement of efficiency: The increased constant velocity universal joint reduces the efficiency, but because the power shaft is not affected by the bending moment force, the end bearing only plays a role, and the original structure requires three heavy-duty bearings to bear the main shaft. The radial force, axial force and bending moment are now simplified to a heavy-duty bearing, and the frictional power consumption is reduced. The new structure is reduced between the oil distribution plate and the speed control plate compared to the original rotor swing speed governing mechanism. The sliding mating surface, the corresponding leakage is reduced, and the volumetric efficiency is improved; thus, the overall efficiency is still higher than the general variable skew pump. DRAWINGS

1 is a schematic structural view of a conventional swash plate pump;

Figure 2 is a cross-sectional view taken along line AA of Figure 1; 3 is a schematic structural view of a conventional oblique shaft pump;

Figure 4 is a schematic structural view of the present invention;

Figure 5 is a front view showing the structure of a first embodiment of the present invention;

Figure 6 is a cross-sectional view taken along line A-A of Figure 5;

Figure 7 is a cross-sectional view taken along line B-B of Figure 6;

8 is a schematic front view showing the structure of Embodiment 2 of the present invention;

Figure 9 is a schematic view showing the assembly structure of the ball cage type constant velocity universal joint;

Figure 10 is an exploded perspective view of a ball cage type constant velocity universal joint.

The main figure description:

1-Shell, 2-Wheel Bearing, 3-Spindle Front Support Bearing, 4- Spindle, 5-Spindle Seal End, 6-Spindle Front Support, 7-Swing, 8-Combination, 9- Spiral swash plate and ball cage constant velocity universal joint outer ring, ball joint and plunger of 10 - ball joint plunger assembly, 11 - ball cage constant velocity universal coupling steel ball and ball Cage and inner ring, 12-million coupling inner ring retaining ring, 13-inlet/outlet port, 14-turn to cylinder block, 15-distribution oil pan, 16-spindle rear support bearing, 17-pressing force Control oil passage, 18-rear cover, 19-pressure spring, 20-out/inlet, 21-pressure spring retaining ring and retaining ring, 22 leaking oil hole, 23-return plate, 24-variable trunnion, 25 - variable trunnion seal end cap, 26 - variable trunnion mount, 27-threaded, 28-variable cylinder, 90-swashplate axis, 41-spindle axis, 111-inner ring, 112-steel ball, 113-retained Shelf, 114-outer ring. detailed description

Referring to FIG. 4, the axial piston pump or motor of the present invention mainly comprises: a housing 1; a main shaft 4 rotatably supported on the housing 1; and a rotor cylinder 14 having a plurality of plunger holes, which are coupled to On the main shaft 4, the main shaft 4 drives it to rotate about the main shaft axis 41, and the rotor cylinder 14 has an oil distribution end face; an oil distribution plate 15 which cooperates with the oil distribution end surface of the rotor cylinder block 14; the swash plate 9, which The end faces are axially disposed opposite the plurality of plunger bores of the rotor cylinder 14 and are rotatable about a swash plate axis 91 at an angle to the spindle axis 41; a plurality of plunger assemblies 10 having one end hinged to the swash plate 9 end faces, the other end slides The movable shaft is disposed in the plunger hole of the rotor rainbow body 14; the constant velocity universal joint 11 is disposed between the swash plate 9 and the main shaft 4, and the constant velocity universal joint 11 is in the main shaft 4 and the rotating shaft The torque is transmitted between the discs 9, and the main shaft 4 and the swash plate 9 are respectively rotated about the spindle axis 41 and the swash plate axis 91 which are disposed at an angle. Thus, when the present invention is used as an axial piston pump, the drive spindle 4 is rotated about the spindle axis 41, and the swash plate 9 can be driven by the constant velocity universal joint 11 around the swash plate at an angle to the spindle axis 41. The rotation of the axis 91 causes the plunger assembly 10 to reciprocate axially within the plunger bore of the rotating cylinder 14, thereby forming a volume change in the rotating rainbow body 14, thereby realizing the process of oil absorption and oil pressure, that is, achieving rotational mechanical energy and Conversion between hydraulic energy. When the present invention is used as an axial piston motor, the swash plate 9 is rotated about the swash plate axis 91 by the hydraulic oil entering the plunger hole, and the spindle 4 is driven around the spindle axis 41 by the constant velocity universal joint 11. Rotating, and simultaneously rotating the rotor cylinder 14 coupled with the main shaft 4, causes the plunger assembly 10 to reciprocate in the plunger bore, thereby converting hydraulic energy into rotational mechanical energy of the main shaft. Since the axial piston pump or motor of the present invention is used as a pump or as a hydraulic motor, its basic structure is the same, and it will be described in detail in the present invention mainly as a pump.

In the present invention, in a specific example, as shown in Fig. 4-7, the casing 1 and the rear end cover 18 are screwed together to form a closed casing; the main shaft 9 is supported by the front and rear bearings 6, 16 In the box. The oil inlet groove and the oil discharge groove on the oil distribution plate 15 are respectively connected to the inlet and outlet ports 13, 20. The main shaft 9 sequentially passes through the oil distribution plate 15, the rotor cylinder 14, the compression spring 19, the constant velocity universal joint 11, the swash plate 9, and protrudes from one end of the casing through the sealed end cover 5. Wherein, the rotor rainbow body 14 is fixed on the main shaft 4 by the flower key, and is pressed on the oil distribution plate 15 by the compression spring 19 sleeved on the main shaft 4, thereby realizing the relationship between the rotor cylinder 14 and the oil distribution plate 15. The initial seal. The spindle 4 rotates, and the swash plate 9 is driven to rotate about the swash plate axis 91 by the constant velocity universal joint 11 while rotating through the spline belt 'moving rotor red body 14 to drive the plunger assembly 10 in the rotor cylinder. The plunger hole of the 4 reciprocates to form a volume change in the plunger hole, and is connected with the inlet and outlet ports 13 and 20 in cooperation with the oil distribution plate 15, thereby realizing the process of oil absorption and oil pressure, that is, realizing Rotation between mechanical energy and hydraulic energy.

In the present invention, the constant velocity universal joint 11 can be a ball cage type, a half angle cage type, a ball joint type, In the present invention, a ball-cranked constant velocity universal joint is mainly described as an example, and other constant velocity universal joints such as a half-angle ball cage and a ball joint are described in detail. Type, ball fork type, etc. Although the structure is relatively complicated compared with the ball cage type universal coupling, as long as the space size allows, it can be used, and will not be detailed here. As shown in Fig. 5 - 10, in the example in which the constant velocity universal joint 11 is a ball cage type constant velocity universal joint, the ball type constant velocity universal joint 11 is composed of an inner ring of an outer ball path. 111, an even number of steel balls 112, a cage 113 and an outer casing 114 with an inner ballway, wherein the outer ring 114 is combined with the swash plate 9, and the inner cymbal 111 is coupled to the main shaft 4 so as to be driven by the main shaft 4 When the ring 111 is rotated about the spindle axis 41, the swash plate 9 coupled with the outer ring 114 can be rotated about the swash plate axis 91 (i.e., the rotational axis of the outer ring 114) having an angle with the spindle axis 41. As a specific example, the outer ring and the swash plate 9^ inner hole may be combined into one to integrally form the outer ring 114 on the swash plate 9 to save radial space size. The inner ring 111 can also be integrated with the main shaft 4 to be integrally formed on the main shaft 4, but in consideration of the processability and the feasibility of installation, it is separately disposed in the present embodiment, and is splined with the main shaft 4 It is fixedly connected and axially positioned by the upper retaining ring 21. As shown in Fig. 9, according to the principle of the ball cage type constant velocity universal joint, the inner circle center and the outer ring center should be located on the spindle axis 41, and equidistantly arranged in the constant velocity universal joint 11 The center points are on both sides. The cage 113 defines an even number of steel balls 112 in the same plane, and the plane also passes through the center point of the coupling.

As an optional specific example, the plurality of plunger assemblies 10 of the present invention may be a ball joint type plunger assembly, which is composed of a ball joint rod and a plunger having a ball end at both ends, and an oil hole is opened in the middle. The pressure head is introduced to lubricate the ball ends at both ends, and the structure is the same as that of the inclined shaft pump. The right end of the swash plate 9 is evenly distributed with a plurality of ball sockets whose center points are located in the same plane, and the ball end of the plunger assembly 10 is embedded and defined by the return disk 23 in the ball socket of the swash plate 9, the plunger assembly 10 The plunger end projects into the plunger bore of the rotor cylinder block 14. The number of plunger assemblies 10 is equal to the number of sockets on the swash plate 9 and the number of plunger holes in the rotor. The center point of the constant velocity universal joint 11 and the center plane of the plurality of balls on the swash plate 9 coincide with the intersection of the spindle axes. '

In the present invention, as shown in FIG. 4-8, the intermediate casing and the front end cover of the casing 1 may be an integral knot. The structure is cast in cast iron or alloyed aluminum, and the rear end cover 18 is connected to the intermediate casing by threads. Of course, other structural forms are also possible. For example, the intermediate casing and the front end cover are separated, and the front end cover and the intermediate casing are screwed together. The overall strength is high and the processing is difficult, while the latter is the opposite, each has its own advantages.

As shown in Fig. 4-7, as an alternative embodiment of the present invention, in the first embodiment, the axial piston pump or motor of the present invention is capable of variable adjustment, and the swash plate 9 can simultaneously The swash plate bearing 8 which is subjected to radial force, axial force and bending moment is embedded in a pendulum case 7, which is supported by the oscillating disc bearing 2 on the housing 1, the axis of rotation of which is perpendicular to The spindle axis 41 passes through the center of the constant velocity universal joint 11, i.e., the wobble plate 7 can only swing about the center of the constant velocity universal joint 11 in a plane parallel to the spindle axis 41; The deflection is adjusted to adjust the inclination angle of the swash plate 9 (i.e., the inclination angle of the swash plate axis 91 with respect to the spindle axis 41), thereby realizing variable adjustment. In the first embodiment, as shown in FIG. 4-7, a variable adjustment mechanism for adjusting the deflection angle of the wobble plate 7 is connected to the wobble plate 7, since the constant velocity universal joint 11 rotates the main shaft 4 The movement and the torque are transmitted to the swash plate 9 which is rotated about the swash plate axis 91. Thus, the variable adjustment of the pump or the motor can be conveniently realized by the variable mechanism driving the wobble plate 7 to swing and change the inclination of the swash plate 9.

As shown in FIG. 4-6, in the first embodiment, the wobble plate 7 is an upper and lower two incomplete cylindrical faces supported by the wobble plate bearing 2 on the casing 1, and the right end has a stepped inner cylindrical surface for embedding. Swash plate bearing 8. As an example of the variable adjustment mechanism, as shown in FIGS. 6-7, the variable adjustment mechanism may be an trunnion external variable adjustment including a trunnion 24 coupled to the wobble plate 7 and a drive mechanism for driving the trunnion 24 to rotate. The axis of rotation of the variable trunnion 24 coincides with the axis of oscillation of the wobble plate 7, thereby effecting variable adjustment by rotating the trunnion 24 by the peripheral drive mechanism. In this example, may be on one side of the wobble plate 7 by the ^screw: variable profile member 27 is attached to the trunnion seat 26, the variable circumferentially trunnion 24 26 is fixedly connected by a spline or a flat key so as to seat the trunnion variable The trunnion 24 is mounted on the wobble plate 7. Thus, turning the trunnion 24 can drive the wobble plate 7 to swing, which is not only simple in structure but also relatively intuitive. As another example of the variable adjustment mechanism, as shown in FIG. 4, the variable adjustment mechanism may also be a variable cylinder 28, the piston of the variable cylinder 28 being coupled to the wobble plate 7, thereby driving the wobble plate 7 to be deflected by the expansion and contraction of the piston. To achieve change Quantity adjustment. Of course, the variable adjustment mechanism can also have many other ways, and the variable mechanism in the various swash plate pumps can be borrowed, as long as the deflection angle of the wobble plate 7 can be changed by the variable adjustment mechanism, which will not be described in detail herein.

As shown in FIG. 5-6, the wobble bearing 2 in Embodiment 1 can be two crescent-shaped needle bearings which are vertically symmetrical, the axis of rotation of which is perpendicular to the axis of the main shaft 4, and passes through the constant velocity universal joint. 11 center. The outer ring of the bearing is fixed to the bearing housing of the housing 1, and the inner ring is fixed to the cylindrical surface of the left end of the wobble plate 7, or is combined with the cylindrical surface. The function of the bearing is to transmit the thrust of the wobble plate 7 to the casing 1 and reduce the swinging resistance of the wobble plate 7. The bearing can also be other types of bearings, such as plain bearings.

In the first embodiment, the left end of the swash plate 9 can be provided with a bell mouth inner hole for the spindle 4 to pass, and does not interfere with the main shaft 4 when swinging with the wobble plate 7, and the left end of the swash plate 9 has an outer cylindrical surface. To install the swash plate bearing 8, the right end plane of the swash plate 9 has a plurality of ball sockets whose center points are located in the same plane, and the number of ball sockets is usually an odd number, such as 5-11, and the center of the right end of the swash plate 9 is a spherical hole. The inner ball path in the direction of the main shaft 4 is engraved as the outer ring of the ball cage type constant velocity universal joint 11.

As shown in Fig. 8, as another embodiment of the present invention, in Embodiment 2, the axial piston pump or motor of the present invention is also applicable to a metering pump, and since the adjustment of the variable is not required, the wobble plate 7 of Embodiment 1 The wobble plate bearing 2 and the variable mechanism can be omitted. The swash plate 7 is directly supported on the inclined surface of the casing 1 through the swash plate bearing 8, and the entire structure will be very simple and compact.

The important friction surface in the present invention can be subjected to coating or coating treatment, such as molybdenum disulfide plating, to reduce friction loss, and to improve efficiency and life.

The swash plate support bearing 8 of the present invention needs to withstand the axial force, the radial force and the turning moment from the swash plate, so that the combined bearing of the needle/cylinder (cone) roller thrust bearing can be selected, and the same can be selected. Other types of bearings or combination bearings that function.

In the present invention, as shown in Figs. 4-6 and 8, the front end of the main shaft 4 is splined or flat-keyed, and is connected to other prime movers or working machines. The main shaft 4 has splines in the middle and the constant velocity universal joint 11 and the rotor cylinder 14 are circumferentially fixedly connected, and the swash plate 9 and the rotor cylinder 14 are rotated to transmit the twist. Moment. The middle of the main shaft 4 supports the disc-shaped compression spring I ⁹ through the compression spring retaining ring 21 and the compression spring seat, and the compression spring 19 can also be a cylindrical coil spring. The preload of the spring is usually calculated using the residual pressure method to ensure a reliable seal between the rotor cylinder 14 and the oil distribution plate 15. In order to more conveniently adjust the pressure between the rotor red body 14 and the oil distribution plate 15, an oil hole and a radial oil passage are opened at the right end of the main shaft 4, and pressure oil is introduced from the pump body to act on the right end surface of the rotor rainbow body 14, and is adjusted. With external pressure oil pressure, the pressure between the rotor block 14 and the oil distribution plate 15 can be adjusted to meet the higher overall efficiency of the pump under different operating conditions.

As shown in Figs. 4-6 and 8, the rotor rainbow body 14 of the present invention may be a cylinder having a plurality of plunger holes circumferentially distributed to form a close dynamic fit with the plunger of the plunger assembly 10. As shown in Fig. 5 and Fig. 8, the oil distribution end face of the rotor body 14 is a spherical surface, which is closely matched with the spherical oil distribution plate. 15 to form a spherical fit, and has a good self-centering effect. The rotor cylinder 14 can be made of copper, ductile iron, cast steel, forged steel, etc., and is worn on the inner surface of the plunger hole and the oil spherical surface, such as nesting or plating. Considering that the constant velocity universal joint 11 needs to be installed in the center of the swash plate 9, the radial dimension of the small displacement pump must be increased. At this time, the rotor rainbow body 14 can be rounded, that is, the diameter of the left end. Larger than the right end, the plurality of plunger holes are also tapered, wherein the diameter of the hole of the plunger hole at the mating end of the plunger assembly 10 (ie, the left end in the drawing) is larger than the other end (in the drawing) The diameter of the circle at the right end of the plunger hole. Thus, it is not necessary to increase the diameter of the red body 14 as a whole, and the diameter of the oil distribution port can be reduced. As shown in Fig. 4, the end face of the rotor rainbow body 14 can also be in the form of a flat surface, which is easy to process.

The structural size characteristics of the present invention will be further explained below in connection with the calculation of the specific parameters of the variable pump described in Embodiment 1 of the present invention having a displacement of 16 1 /r and a rated pressure of 35 MPa.

5厘米。 The plunger has a diameter of 12 - 13mm, the effective volume of each plunger is 2. 3ml, the maximum stroke of the Haoshen is 1. 8-2. Ocm, the diameter of the plunger is 12 - 13mm. The diameter of the circumference of the center of the plunger is determined by the swing angle of the wobble plate 7. According to experience, the swing angle is 20 degrees, and the diameter of the circumference of the plunger center can be calculated to be 56 mm. The outer diameter of the rotor cylinder 14 is 75 legs x 40 mm. The output torque of the pump is 8 ⁹ Nm, and the diameter of the power shaft (spindle 4) made of ordinary steel material is I ⁵ - 2 Oram. Taking into account the strength of the constant velocity universal joint 11 itself, size and angle limits, and the strength of the power shaft And the rigidity, the rotor rainbow body 14 is formed into a 雉 shape, the rotor has a large end diameter of 82 faces, the small end diameter is 72 瞧, the swash plate 9 has a diameter of 85 mm, and the wobble plate 7 has a diameter of 100 mm, and the entire pump is sized. For 120 hidden X 150 let (without shaft end extended length). Obviously, the size and weight of the pump is smaller than that of the same displacement swash pump, and much smaller than the inclined shaft pump.

Claims

Claim

1. An axial piston pump or motor comprising:

Housing

a spindle that is rotatably supported on the housing;

a rotor rainbow body having a plurality of plunger holes, which is coupled to the main shaft, is driven by the main shaft to rotate about the main shaft, and the rotor cylinder has an oil distribution end surface;

An oil distribution plate, which cooperates with an oil distribution end surface of the rotor red body;

The constant velocity universal joint is disposed between the swash plate and the main shaft, and the constant velocity universal joint transmits torque between the main shaft and the swash plate, and the main shaft and the swash plate are respectively disposed at an angle The set spindle axis and the swashplate axis rotate.

2. The axial piston pump or motor according to claim 1, wherein the constant velocity universal joint is a ball cage type constant velocity universal joint, a half angle cage type constant velocity universal joint Couplings, ball joint type constant velocity universal joints or ball fork type constant velocity universal joints.

3. The axial piston pump or motor of claim 2, wherein the ball-ghost constant velocity universal joint comprises an inner ball with an outer ballway, an even number of steel balls, a cage, and An outer ring with an inner ballway, the steel ball is mounted on the cage and located in the inner and outer fairways, the inner ring is coupled to the main shaft, and the outer ring is coupled to the swash plate to pass the ball The cage constant velocity universal joint rotates the main shaft and the swash plate around the spindle axis and the swash plate axis at an angle.

The axial piston pump or motor according to claim 3, wherein said outer ring is integrally formed on the swash plate.

5. The axial piston pump or motor of claim 1 wherein said swash plate is supported on the housing by a swash plate bearing.

6. The axial piston pump or motor according to claim 1, wherein the swash plate is supported on a wobble plate by a swash plate bearing, and the wobble plate is supported by the wobble plate bearing Body, the axis of rotation of the wobble plate shaft is perpendicular to the spindle axis and passes through the center of the constant velocity universal joint.

The axial piston pump or the horse according to claim 6, wherein a variable adjustment mechanism for adjusting a deflection angle of the wobble plate is connected to the wobble plate, thereby passing a deflection angle of the wobble plate. The change changes the angle between the axis of the swash plate and the main shaft of the swash plate supported thereon.

8. The axial piston pump or motor according to claim 7, wherein the variable adjustment mechanism is a variable oil cylinder, and the plug of the variable oil cylinder is coupled to the wobble plate so as to be expanded and contracted by the piston. The drive wobble plate is deflected.

9. An axial piston pump or motor according to claim 7 wherein said variable adjustment mechanism is an trunnion type variable mechanism comprising a trunnion coupled to the wobble plate and a drive for driving the trunnion to rotate The mechanism, the axis of rotation of the trunnion coincides with the axis of rotation of the wobble plate, thereby driving the wobble plate deflection by rotating the trunnion. ,

The axial piston pump or motor according to claim 1, wherein said rotor cylinder is tapered, and a diameter of one end adjacent to the swash plate is larger than a diameter of the other end.

11. The axial piston pump or motor of claim 10, wherein the plurality of plunger holes in the rotor body are also tapered.

12. The axial piston pump or motor of claim 1 wherein said plunger assembly is a ball jointed plunger assembly including a ball joint and a plunger having ball ends at both ends a ball socket is arranged on the swash plate, and a ball end of the ball end link is disposed in the ball socket to form a ball joint connection with the swash plate, and the other end ball head is disposed in the plunger to form a ball with the plunger 3⁄4, the plunger slides in the plunger hole.

13. The axial piston pump or motor according to claim 12, wherein an oil hole communicating with the plunger hole is opened in the middle of the ball joint and the plunger, thereby introducing pressure oil to lubricate both ends Ball head.

14. The axial piston pump or motor of claim 1 wherein: said plurality of plunger assemblies are located on a same plane on a hinge center of the swash plate, and the plane and the spindle axis The intersection coincides with the center of the constant velocity universal joint.

15. The axial piston pump or motor according to claim 1, wherein the rotor cylinder is axially positioned on the main shaft by a compression spring and a compression spring retaining ring, and an oil hole is formed at an end of the main shaft. A radial oil passage that regulates the pressure between the rotor cylinder and the oil distribution plate by injecting pressurized oil into the radial oil passage.

The axial piston pump or motor according to claim 1, wherein the oil distribution end surface of the rotor cylinder is a spherical surface, and the oil distribution plate of the rotor body forms a spherical fit with the oil distribution end surface.

The axial piston pump or motor according to claim 5 or claim 6, wherein said swash plate bearing is a combined bearing of a needle bearing and a cylindrical or tapered roller thrust bearing.

18. An axial piston pump or motor according to claim 6 wherein said wobble plate bearing is a crescent-shaped needle bearing.